Slartibartfast

It's the dizzy itself that goes, unfortunately.

Good to hear it was an easy fix! And yeah, those little clips holding the air grilles on are weak sauce. I gave up on mine and used black zip ties.

Jesus! Hopefully the new one holds up.

Interesting. I hadn't thought about polarity when I did the caps on mine. Makes sense, though! How's it sound?

First I've heard of this. Any idea what was supposed to be wrong? Do you know if the recall had some kind of reference number or something? That might help your case. I'd be surprised if the dealer was interested in looking up a recall they've never heard of on a twenty-three year old vehicle.

Higher octane fuel shouldn't be a problem. The computer probably didn't notice anything different. Sounds like an electrical issue to me, something starting to go out. Anything else you notice when it's running poorly? Smells, smoke?

My understanding is that a worn CV doesn't tend to make noise unless you're loading it, so I'd expect it to make more noise in 4x, not less. And unless the boots are blown up, or the joint has failed catastrophically, they can make loads of noise and look fine. SMA on Youtube did a teardown on a really noisy one recently and didn't find the problem with the axle until he had it completely to pieces. Are you sure you put the snap rings back on when doing the hubs? Maybe the shafts are trying to float inwards and binding up?

If you're curious, here's Nissan's tech bulletin for identifying and... I can't bring myself to say repairing the strut towers, because I've read it. The bulletin might give you some idea of what Nissan considers terminal, though, which could help you gauge how bad yours is and what areas you need to worry about as far as structure. Hopefully your fab guy can repair the damage properly. Good luck!

Sounds more like something loose in the suspension to me. Having it in 4WD might be loading up whatever is making the thunk and changing the noise it makes. That said, having it thunk like you hit something sounds like it might be something more serious in the drivetrain.

Some R50s have load sensing valves near the rear axle. I don't remember what year they quit using those, but this guy had a hell of a time getting air out of his brakes until he got the bleeder on his LSV cracked loose. Something to check. I've seen a bunch of bubbles come down a brake bleed line recently when I was bleeding an F150. When I pressed the pedal, fluid came out; when I didn't press the pedal, I got bubbles. The brakes felt fine when I shut the bleeder. I think what was happening was that the fluid trying to go down the hose I had on the bleeder was drawing in air around the bleeder threads. Maybe I had the bleeder threaded out too far, maybe the threads were just cut (or worn) loose. Either way, I don't think the bubbles were coming from inside the caliper.

If you want to test compression to rule out the belt, you wouldn't have to test each cylinder. If the belt slipped on the crank, all cylinders would be affected equally. Check the easiest one to get at, and if it's got good squish, I'd say it's not the belt. I don't know what would've gotten in there, either; it's just the only thing I could think of that wasn't fuel or spark. Orange spark makes me more suspicious of the coil. I'd start there.

Does the issue come and go as you plug and unplug the dash cam, or with other loads on the cigarette lighter? I don't know offhand which fuse links go where, but I'd check to see if those look alright; maybe one's corroded and the additional load of the dash cam is enough to sap power from the ECU and TCU and screw things up. Or, if it only goes haywire with the camera, and not other loads, maybe your dashcam is just a noisy SOB. Tire size can throw off the speedo but 4mph across the board sounds like it's just out of adjustment. You could probably just open up the cluster, remove the needle, and put it back 4mph lower, though of course this would be tricky to gauge correctly with the cluster out. I'd be inclined to leave it alone, until you figure out the other issue, on the off chance that fixing one clears up the other.

If you or someone you know has a code scanner (you can get them pretty cheap), check for codes. This might give you some idea of what you're up against, if the issue is electrical. It might just be a failed sensor or a bad connection. When you try to start it, does it try to catch at all? Or does it just crank like it's out of gas? Spark but no fire, even on starting fluid, is odd. Is it a strong blue spark or a weak orange one? If it's got good spark, it should kick on starting fluid, unless it's got no compression or it's timed wrong. Given the recent timing job, it shouldn't be the belt, and fire on all six tells me the distributor is still spinning. That said, if the computer doesn't have any bright ideas, I'd turn the engine to TDC (check the marks on the crank pulley, or stick a dowel or a rod down the #1 spark plug hole) and check the position of the rotor. It should point roughly at where either the #1 or #4 spark plug wire goes. If something fell into the belt (not sure what it would be), and it skipped a couple of teeth, that would screw up your timing and your compression at the same time. Hopefully it's not that.

I don't think he's talking about the tranny cooler leaking coolant. There's some kind of bizarre oil cooler on the VQ R50s that transfers engine oil heat to the coolant (near as I can tell). Apparently the O-rings tend to fail and leak oil. If it's leaking coolant, either it's actually the hose that's leaking or the cooler's hooped. Looks like you can get one for about $80 on Fleabay if the cooler itself is bad. More on this.

If you remove your clamshell (carefully, they tend to be brittle and half-busted already) you'll find the connections at the back of the ignition cylinder. Big bright solder blobs, can't miss 'em. The one with the black/yellow wire is the starter. I don't remember which is constant +, but you should be able to find it easily enough with a test light. Jumper the starter wire to constant + and it should crank. If it cranks when jumpered, but not with the key, then yeah, your ignition contacts are shot. The manual trans rigs have a proper starter relay that switches power to the starter, and the ignition switch just makes that relay click. The auto trans rigs make the switch carry full power. (There is an inhibitor relay on the AT rigs, but it just breaks the circuit if you've got the trans in gear.) The contacts in the switch wear to where they can't pass enough power to make the starter solenoid go. Some guys have had good luck just adding a starter relay to their AT rigs; the switch may be too worn to power the solenoid, but it might still have enough life in it to power a relay coil. I tried this on a friend's Yota and it worked for a while but ended up stranding her again, so I can't really recommend it as a fix. The proper fix would be a new ignition switch; we cheaped out and converted it to push-button start instead.

Jesus man, sorry to hear that. Hopefully it stays in remission and lets you get back to your projects.

Yours looks a little different underneath than mine! Good luck getting the bugger lined up.

Now that's an orange motor! Does the P stand for powder coat by any chance?

Update on the SMOD R51. Turns out it's also got 8psi oil pressure at idle when it's warm. Apparently the VQs have an oil galley behind the rear timing cover, sealed from it by a gasket which can fail and piss away oil pressure through the timing cover. Either it's that, or the pump and bearings are somehow whupped at 143k miles. Either way, it needs significant engine work on top of its transmission woes and the godawful mayonnaise mess. The mechanic's estimate pretty well punched the truck's ticket to the wreckers. Anyone near eastern Washington need an R51 for parts? Looks like a clean shell, anyway. Oh, and my mini-writeup for my janky lighting mod is up on my build thread.

It was pretty simple, actually. I'll post a few pictures of the process in my build thread later. It's more than a bit on the redneck side LOL but it's all hidden behind the trim.

The rubber elbows on the injector rails tend to leak. Happened on my '95. Tightening the hose clamps (they're tricky to get to but not bad once you figure out where they are) solved the problem.

I modded my tailgate so that when I open the hatch glass to grab something, the interior lights come on automatically. This should save me my usual dance of opening the glass, groping for the light switch, grabbing whatever I'm after, shutting the glass, and then digging out my keys again because I forgot to turn the stupid light back off. I'm less annoyed by the WD's quirks than usual, though. Family friends with an R51 visited yesterday and said theirs was kind of bucking and jumping on the way here. My dad and I checked fluids and sure enough, it's got the SMOD. The trans dipstick looked/smelled alright but the radiator's full of creamy greyish-pink nope. We're hoping we caught it soon enough to save the tranny.

Here's the tranny mount itself. The two sides of it are shaped differently. The one with an edge facing the ground is on the trans side, and the one with a 90° bend facing the crossmember is on the transfer case side. Here's the driver's side where the crossmember meets the frame, looking forwards (frame rail on the left, exhaust pipe on the right). I'm noticing the frame mount has extra holes in it--possibly for mounting a different crossmember? Or mounting the same one shifted back a bit for some reason? I don't know if it's even possible to bolt to those holes, but if it is, and you did, that could be why your trans mount isn't lining up. And the passenger's side, also with an extra hole showing just behind the crossmember. (The lot of these are at https://www.flickr.com/photos/158412646@N06/with/39419842172/ if they're not showing or you want higher res or something.) I took a rough measurement bolt center to bolt center (eyeballing center) and got around 3.58 cm (probably more like 3.6cm, looking at how centered that left jaw isn't). This measurement appears the same on driver's and passenger's sides. Let me know if any of this is what you're after, or if you need more/better measurements.

I can't help on the 2WD but I'll see if I can get a shot of mine when it's not caked in snow. You're looking at the crossmember between the transmission pan and the transfer case, right?

You might jack it up and spin the front left by hand and just see if you can feel or hear any CV noise or bearing play. Might also be good to check a few fasteners, make sure the alignment shop didn't leave something loose. I had some issues with the transfer in my '95 not wanting to leave 4x and a flush and fill solved it. I didn't have your rumbling issues, though. Does sound driveshaft-related to me, though that doesn't explain the pulling or, unless I'm missing something here, the slow disengagement of the transfer.